Lasiodiplodia mali Yanfen Wang & M. Zhang, sp. nov. Fig. 17
MycoBank number: MB 843627; Index Fungorum number: IF 843627; Facesoffungi number: FoF 12934;
Etymology: Name refers to Malus pumila, the host genus from which this fungus was collected.
The sexual stage was not observed. Conidiomata pycnidial, produced on pine needles on WA within 2–3 wk, solitary or aggregated, individual conidiomata globose or irregular, superficial, covered with dense mycelium, uniloculate, exuding conidia in a yellow mucoid mass, up to 640 μm high, up to 910 μm wide. Paraphyses cylindrical, hyaline, thin-walled, initially aseptate, becoming septate when mature, rounded at apex, up to 56 μm long. Conidiophores absent. Conidiogenous cells holoblastic, hyaline, cylindrical, smooth, (7.5–)8.5–12.5(–14) × (3–)3.5– 4.5(–5) μm. Conidia initially hyaline, ellipsoid to ovoid, with granular content, aseptate, wall 1–2 μm, becoming pigmented, ellipsoid to ovoid, 1-septate with longitudinal striations, (21–)22–24.5(–26) × (11.5–)12–13(–14) μm (av. = 23.2 × 12.6 μm, n = 50; L/W = 1.8).
Material examined: CHINA, Henan Province, Zhengzhou City, from stems of apple, fruiting structures induced on needles of Pinus sp. on water agar, 1 Jun. 2021, Y.F. Wang & M. Zhang (holotype HMAS 351912, culture ex-type CDZM 099 = CGMCC 3.20840); Zhengzhou City, from branches of grapevine, 12 Jun. 2021, Y.F. Wang & M. Zhang (culture CDZM 072); Zhengzhou City, from branches of walnut, 10 Jun. 2021, Y.F. Wang & M. Zhang (culture CDZM 161 and CDZM 162).
Sequence data: ITS: OL863167 (ITS1/ITS4); EF1a: OM243813 (728F/986R); TUB2: OM228626 (Bt2A/Bt2B); RPB2: OM243837 (RPB2-LasF/ RPB 2-LasR)
Notes: Lasiodiplodia mali forms an independent clade and is phylogenetically closely related to L. nanpingensis, L. citricola and L. paraphysoides, but can be distinguished from each other based on conidial morphology. Conidia of L. mali (av. 23.2 × 12.6; L/W = 1.8) are smaller than those of L. citricola (av. 24.5 × 15.4, L/W = 1.6) (Abdollahzadeh et al. 2010) and L. nanpingensis (av. 23.9 × 14.8, L/W = 1.6) (Wang et al. 2021), but slightly longer and narrower than L. paraphysoides (av. 23.0 × 13.7, L/W = 1.69) (Wang et al. 2021). In addition, the paraphyses of L. mali (56 μm) shorter than L. nanpingensis (102 µm), L. citricola (125 µm) and L. paraphysoides (125 µm). This species differed by nucleotide sequences in tef1 (tef1 is not available to L. nanpingensis, L. citricola: 1 bp and 1 indel, L. paraphysoides: 3 bp), tub2 (L. nanpingensis: 1 bp, L. citricola: 2 bp, L. paraphysoides: 1 bp and 1 indel) and rpb2 (L. nanpingensis: 1 bp, L. citricola: 1 indel, L. paraphysoides: 1 indel).
Fig. 17 Lasiodiplodia mali. a–d. colony growing on front and back of PDA (a, b) and MEA (c, d); e–f. conidiomata on PNA; g–h. section view of conidiomata; i–j. paraphyses; k–l. brown, 1-septate mature conidia; m–n. hyaline conidia; o. conidiogenous cells and developing conidia. — Scale bars: e–f = 500 μm; g = 100 μm; h–i = 20 μm; j–o = 10 μm.